RESUMEN
BACKGROUND: There is an interest in finding new and safe antioxidants from natural sources such as medicinal plants. OBJECTIVES: The aim of this study was to evaluate the antioxidant activity of ten Iranian medicinal plants extracts. MATERIALS AND METHODS: For antioxidant activity, the radical scavenging activity, reducing power and phenolic contents of ethanol plant extracts were determined. Gallic acid was used as standard reference with well-documented antioxidant activity. RESULTS: The highest antioxidant activity in terms of DPPH radical scavenging was found in Verbascum sinuatum L. Var (VS) with an IC50 equal to 263.52 ± 5.981 µg/ml and Rosa damascena Mill (RD) with and IC50 equal to 287.9 ± 5.675 µg/ml that are higher than gallic acid (IC50 = 25.32 ± 5.593 µg/ml). The highest antioxidant activity in terms of ferric reducing capacity was also found in Verbascum sinuatum L. Var extracts (in 85.08 ± 8.66 µg/ml concentration with absorbance 0.5). Also, this extract contains the highest phenolic compounds (8.53 ± 0.11 mg/g). CONCLUSION: In this study, Verbascum sinuatum L. Var contains the highest level of phenolic compounds may be contribute to higher free radical scavenging activity and reducing power in comparison to the other plant extracts. Therefore this plant is a good candidate as natural antioxidant.
